/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.db.mpp.plan.planner.plan.node.write;

import org.apache.iotdb.common.rpc.thrift.TRegionReplicaSet;
import org.apache.iotdb.commons.exception.IllegalPathException;
import org.apache.iotdb.commons.partition.DataPartition;
import org.apache.iotdb.commons.path.PartialPath;
import org.apache.iotdb.commons.path.PathDeserializeUtil;
import org.apache.iotdb.db.mpp.common.schematree.DeviceSchemaInfo;
import org.apache.iotdb.db.mpp.common.schematree.ISchemaTree;
import org.apache.iotdb.db.mpp.plan.analyze.Analysis;
import org.apache.iotdb.db.mpp.plan.planner.plan.node.*;
import org.apache.iotdb.db.wal.buffer.IWALByteBufferView;
import org.apache.iotdb.db.wal.buffer.WALEntryValue;
import org.apache.iotdb.db.wal.utils.WALWriteUtils;
import org.apache.iotdb.tsfile.utils.ReadWriteIOUtils;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.*;
import java.util.stream.Collectors;

import static org.apache.iotdb.commons.conf.IoTDBConstant.MULTI_LEVEL_PATH_WILDCARD;
import static org.apache.iotdb.db.mpp.plan.planner.plan.node.write.InsertNode.NO_CONSENSUS_INDEX;

public class DeleteDataNode extends WritePlanNode implements WALEntryValue {
    /**
     * byte: type, integer: pathList.size(), long: deleteStartTime, deleteEndTime, searchIndex
     */
    private static final int FIXED_SERIALIZED_SIZE = Short.BYTES + Integer.BYTES + Long.BYTES * 3;

    private final List<PartialPath> pathList;
    private final long deleteStartTime;
    private final long deleteEndTime;

    /**
     * this index is used by wal search, its order should be protected by the upper layer, and the
     * value should start from 1
     */
    protected long searchIndex = NO_CONSENSUS_INDEX;

    private TRegionReplicaSet regionReplicaSet;

    public DeleteDataNode(
            PlanNodeId id, List<PartialPath> pathList, long deleteStartTime, long deleteEndTime) {
        super(id);
        this.pathList = pathList;
        this.deleteStartTime = deleteStartTime;
        this.deleteEndTime = deleteEndTime;
    }

    public DeleteDataNode(
            PlanNodeId id,
            List<PartialPath> pathList,
            long deleteStartTime,
            long deleteEndTime,
            TRegionReplicaSet regionReplicaSet) {
        super(id);
        this.pathList = pathList;
        this.deleteStartTime = deleteStartTime;
        this.deleteEndTime = deleteEndTime;
        this.regionReplicaSet = regionReplicaSet;
    }

    public List<PartialPath> getPathList() {
        return pathList;
    }

    public long getDeleteStartTime() {
        return deleteStartTime;
    }

    public long getDeleteEndTime() {
        return deleteEndTime;
    }

    public long getSearchIndex() {
        return searchIndex;
    }

    /**
     * Search index should start from 1
     */
    public void setSearchIndex(long searchIndex) {
        this.searchIndex = searchIndex;
    }

    @Override
    public List<PlanNode> getChildren() {
        return new ArrayList<>();
    }

    @Override
    public void addChild(PlanNode child) {
    }

    @Override
    public PlanNode clone() {
        return new DeleteDataNode(getPlanNodeId(), pathList, deleteStartTime, deleteEndTime);
    }

    @Override
    public int allowedChildCount() {
        return NO_CHILD_ALLOWED;
    }

    @Override
    public List<String> getOutputColumnNames() {
        return null;
    }

    @Override
    public int serializedSize() {
        int size = FIXED_SERIALIZED_SIZE;
        for (PartialPath path : pathList) {
            size += ReadWriteIOUtils.sizeToWrite(path.getFullPath());
        }
        return size;
    }

    @Override
    public void serializeToWAL(IWALByteBufferView buffer) {
        buffer.putShort(PlanNodeType.DELETE_DATA.getNodeType());
        buffer.putLong(searchIndex);
        buffer.putInt(pathList.size());
        for (PartialPath path : pathList) {
            WALWriteUtils.write(path.getFullPath(), buffer);
        }
        buffer.putLong(deleteStartTime);
        buffer.putLong(deleteEndTime);
    }

    public static DeleteDataNode deserializeFromWAL(DataInputStream stream) throws IOException {
        long searchIndex = stream.readLong();
        int size = stream.readInt();
        List<PartialPath> pathList = new ArrayList<>(size);
        for (int i = 0; i < size; i++) {
            try {
                pathList.add(new PartialPath(ReadWriteIOUtils.readString(stream)));
            } catch (IllegalPathException e) {
                throw new IllegalArgumentException("Cannot deserialize InsertRowNode", e);
            }
        }
        long deleteStartTime = stream.readLong();
        long deleteEndTime = stream.readLong();

        DeleteDataNode deleteDataNode =
                new DeleteDataNode(new PlanNodeId(""), pathList, deleteStartTime, deleteEndTime);
        deleteDataNode.setSearchIndex(searchIndex);
        return deleteDataNode;
    }

    public static DeleteDataNode deserializeFromWAL(ByteBuffer buffer) {
        long searchIndex = buffer.getLong();
        int size = buffer.getInt();
        List<PartialPath> pathList = new ArrayList<>(size);
        for (int i = 0; i < size; i++) {
            try {
                pathList.add(new PartialPath(ReadWriteIOUtils.readString(buffer)));
            } catch (IllegalPathException e) {
                throw new IllegalArgumentException("Cannot deserialize InsertRowNode", e);
            }
        }
        long deleteStartTime = buffer.getLong();
        long deleteEndTime = buffer.getLong();

        DeleteDataNode deleteDataNode =
                new DeleteDataNode(new PlanNodeId(""), pathList, deleteStartTime, deleteEndTime);
        deleteDataNode.setSearchIndex(searchIndex);
        return deleteDataNode;
    }

    @Override
    protected void serializeAttributes(ByteBuffer byteBuffer) {
        PlanNodeType.DELETE_DATA.serialize(byteBuffer);
        ReadWriteIOUtils.write(pathList.size(), byteBuffer);
        for (PartialPath path : pathList) {
            path.serialize(byteBuffer);
        }
        ReadWriteIOUtils.write(deleteStartTime, byteBuffer);
        ReadWriteIOUtils.write(deleteEndTime, byteBuffer);
    }

    @Override
    protected void serializeAttributes(DataOutputStream stream) throws IOException {
        PlanNodeType.DELETE_DATA.serialize(stream);
        ReadWriteIOUtils.write(pathList.size(), stream);
        for (PartialPath path : pathList) {
            path.serialize(stream);
        }
        ReadWriteIOUtils.write(deleteStartTime, stream);
        ReadWriteIOUtils.write(deleteEndTime, stream);
    }

    public static DeleteDataNode deserialize(ByteBuffer byteBuffer) {
        int size = ReadWriteIOUtils.readInt(byteBuffer);
        List<PartialPath> pathList = new ArrayList<>(size);
        for (int i = 0; i < size; i++) {
            pathList.add((PartialPath) PathDeserializeUtil.deserialize(byteBuffer));
        }
        long deleteStartTime = ReadWriteIOUtils.readLong(byteBuffer);
        long deleteEndTime = ReadWriteIOUtils.readLong(byteBuffer);

        PlanNodeId planNodeId = PlanNodeId.deserialize(byteBuffer);
        return new DeleteDataNode(planNodeId, pathList, deleteStartTime, deleteEndTime);
    }

    @Override
    public <R, C> R accept(PlanVisitor<R, C> visitor, C context) {
        return visitor.visitDeleteData(this, context);
    }

    @Override
    public TRegionReplicaSet getRegionReplicaSet() {
        return regionReplicaSet;
    }

    public void setRegionReplicaSet(TRegionReplicaSet regionReplicaSet) {
        this.regionReplicaSet = regionReplicaSet;
    }

    public String toString() {
        return String.format(
                "DeleteDataNode-%s[ Paths: %s, Region: %s ]",
                getPlanNodeId(),
                pathList,
                regionReplicaSet == null ? "Not Assigned" : regionReplicaSet.getRegionId());
    }

    @Override
    public List<WritePlanNode> splitByPartition(Analysis analysis) {
        ISchemaTree schemaTree = analysis.getSchemaTree();
        DataPartition dataPartition = analysis.getDataPartitionInfo();

        Map<TRegionReplicaSet, List<PartialPath>> regionToPatternMap = new HashMap<>();

        for (PartialPath pathPattern : pathList) {
            if (pathPattern.getTailNode().equals(MULTI_LEVEL_PATH_WILDCARD)) {
                splitPathPatternByDevice(
                        pathPattern, pathPattern, schemaTree, dataPartition, regionToPatternMap);
            }
            splitPathPatternByDevice(
                    pathPattern.getDevicePath(), pathPattern, schemaTree, dataPartition, regionToPatternMap);
        }

        return regionToPatternMap.keySet().stream()
                .map(
                        o ->
                                new DeleteDataNode(
                                        getPlanNodeId(), regionToPatternMap.get(o), deleteStartTime, deleteEndTime, o))
                .collect(Collectors.toList());
    }

    private void splitPathPatternByDevice(
            PartialPath devicePattern,
            PartialPath pathPattern,
            ISchemaTree schemaTree,
            DataPartition dataPartition,
            Map<TRegionReplicaSet, List<PartialPath>> regionToPatternMap) {
        for (DeviceSchemaInfo deviceSchemaInfo : schemaTree.getMatchedDevices(devicePattern)) {
            PartialPath devicePath = deviceSchemaInfo.getDevicePath();
            // todo implement time slot
            for (TRegionReplicaSet regionReplicaSet :
                    dataPartition.getDataRegionReplicaSet(
                            devicePath.getFullPath(), Collections.emptyList())) {
                // regionId is null when data region of devicePath not existed
                if (regionReplicaSet.getRegionId() != null) {
                    regionToPatternMap
                            .computeIfAbsent(regionReplicaSet, o -> new ArrayList<>())
                            .addAll(pathPattern.alterPrefixPath(devicePath));
                }
            }
        }
    }
}
